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  <title>鼠标点击弹出爱心特效</title>

  <style>
    html {
      width: 100%;
      height: 100%;
      margin: 0;
      padding: 0;
    }

    body {
      width: 100%;
      height: 100%;
      margin: 0;
      padding: 0;
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    div.bg {
      width: 100%;
      height: 100%;
      background-color: rgb(245, 252, 252);
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</head>

<body>
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  <script>
    // JavaScript：立即执行函数 ： https://juejin.cn/post/6969564271541747749
    // ()，！，+，-，=等运算符都能起到立即执行的作用，这些运算符的作用就是将匿名函数或函数声明转换为函数表达式。
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      var s = [];

      // window.requestAnimationFrame() 告诉浏览器——你希望执行一个动画，并且要求浏览器在下次重绘之前调用指定的回调函数更新动画。
      // 该方法需要传入一个回调函数作为参数，该回调函数会在浏览器下一次重绘之前执行。
      e.requestAnimationFrame = e.requestAnimationFrame || e.webkitRequestAnimationFrame || e
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</body>

</html>